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Cost Segregation Experiences?
I purchased a four unit building last year for $350K and replaced the roof. I'm looking to get a cost segregation done and I got several quotes from Cost Seg Guys, Seneca, etc.
Seneca was estimating a reduction in my taxable income by $75-95k.
CSSI was estimating a reduction of $40-60K which is a significant amount less. They told me they like to under promise in overdeliver, but I don't want to move forward with somebody that is telling me on their estimate that I will get a reduction of half of whatever every other company is telling me..
any experience with these companies?
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The 2x spread is almost always a methodology difference. Engineering-based studies (RCNLD, per IRS Pub 5653) identify every component individually. Survey-based studies apply rule-of-thumb percentages to a basis total. Same inputs, very different outputs.
Sanity check on your numbers: $350K 4-plex, ~20% land = ~$280K depreciable basis. A 4-plex typically reclassifies 28-38% into 5/15-year buckets because you're multiplying unit-level components by four (4 kitchens, 4 bathrooms, 4 sets of appliances and flooring). That's $78K-$106K reclassified.
Your higher quote lands in that band. Your lower quote is ~14-21% reclassification — conservative for a 4-unit, which could reflect either a survey methodology or a more defensive classification approach. Worth asking them directly why their number is lower than the typical range for a 4-plex.
Before you pick, ask BOTH firms:
1. Engineering-based (RCNLD) or survey methodology?
2. Site visit or desk study from photos?
3. What % of basis is reclassified and into which specific buckets?
4. Sample redacted report so your CPA can review the format?
5. Audit support policy if the IRS challenges it?
6. Critical for your situation: are you including a partial disposition election for the old roof you replaced? If the old roof had undepreciated basis when you removed it, you can write off the remaining basis as a loss in the year of replacement. This is a separate election from cost seg, but any competent firm handles it in the same engagement. Typically $10-20K of additional Year-1 deduction that most initial quotes don't include.
"Under-promise, over-deliver" isn't necessarily bad — it often reflects a conservative audit posture. But make sure you understand WHY they're lower. Methodology rigor is defensible. Rule-of-thumb padding is leaving money on the table.
Ask both firms for a sample redacted report and pick the one your CPA would actually want to hand to the IRS. The winning study looks like an engineering document (component tables, line-item detail, case-law citations, MACRS schedules), not a short summary memo.


